For many years agricultural balers have been used to consolidate and package crop material so as to facilitate the storage and handling of the crop material for later use. A mower-conditioner typically cuts and conditions the crop material for windrow drying in the sun. When the cut crop material is properly dried, an agricultural harvester, such as a round baler, operates over the windrows to pick up the crop material and form the crop material into cylindrically-shaped round bales. Other agricultural harvesters, such as those harvesters used for biomass collection, use direct feed mechanisms that cut, collect, and bale material into a round bale in sequential steps.
The pickup of the baler gathers the cut and windrowed crop material from the ground then convey the cut crop material into a bale-forming chamber within the baler. A drive mechanism operates to activate the pickup, auger, and a rotor of the feed mechanism. A conventional baling chamber may consist of a pair of opposing sidewalls with a series of belts that rotate and compress the crop material into a cylindrical shape.
When the bale has achieved a desired size and density, a wrapping system may wrap the bale to ensure that the bale maintains its shape and density. For example, a net may be used to wrap the bale of crop material. A cutting or severing mechanism may be used to cut the net once the bale has been wrapped. The wrapped bale may be ejected from the baler and onto the ground by, for example, raising a tailgate of the baler. The tailgate is then closed and the cycle repeated as necessary and desired to manage the field of cut crop material.
The tailgate of the baler typically houses a simple door or panel that is affixed to the tailgate by hinges. In one position, the door or panel remains closed to prevent escape of the harvested bale. In another position, the door or panel can be placed in an open position to facilitate the exit of the harvested bale. Conventional balers require a relatively long period of downtime, typically in the range of between 10 and 15 seconds, to open the door or panel during operation and evacuation of the bale. The downtime required to operate the door reduces the overall efficiency of the harvesting system and interrupts continuous harvesting. The simple door or panel mechanism typically operates very slowly in a manual or automatic fashion. Once fully open the weight of the door or panel is typically very heavy, which affects the center of gravity of the equipment, puts additive stress on the tension points, and may cause instability problems if the agricultural harvester is on a hill or slope.
Modified balers have been designed to address delays caused by ejection. EP 2 220 929 discloses a round baler with a bale chamber and a storage chamber. Bales are condensed and wrapped in the bale chamber, and a fully-formed bale may be stored in and eventually ejected from the storage chamber while harvesting continues to take place in the bale chamber. A harvesting assembly centrally located on the bottom of the harvester routes harvested crop to one of the two chambers. The harvesting assembly in conjunction with an internal series of rollers between the two chambers routes harvested crop through a curved passage that back-feeds the bale chamber on a single moveable roller. A limitation of this design is the multiple directions toward which the harvested crop must be fed from the harvesting assembly causing a greater likelihood of clogging the entry point of the bale chamber. The likelihood of clogging the passage with crop also increases with the work of the back-feed mechanism being completed by a single roller. Another problem is the conventional means to eject the bale from the harvester.
U.S. Pat. No. 6,729,118 discloses another modified baler for harvesting in which three movable arms in operable connection to movable rollers. The moveable arms rotate about the same axis in a windmill-like fashion within the interior of the baler. A pick-up assembly directs crop to only one bale chamber entry point and the windmill-like motion of the arms conveys a bale to a second position within the harvester immediately prior to ejection. This design allows for fewer rollers in the interior of the harvester which are necessary to transfer a partially formed bale to a second position while bale formation occurs near the bale chamber entry point. A potential problem with the design is the control of the independent movement of the arms which may increase operator error during operation. Another limitation of the design is the increased likelihood of silage pile-up and plugging of bale chamber due to a lack of sufficient tension around the bale chamber due to a long belt and long belt pathway. This problem is likely exacerbated by the movable roller mechanically linked to a spring at the front end of the baler. Increased silage and harvested crop pile-up toward the front of the baler may contribute to the bale not forming properly while the baler is in operation due to the lack of tension on the bales caused by the movable roller and its related spring-loaded apparatus.
In some previous designs, for instance U.S. patent application Ser. No. 13/472,266, a conveyor between two bale chambers facilitated movement, however, this design relied solely upon gravity and the downward pitch of the conveyor to transfer a formed bale from one position to another position prior to its evacuation. The instantly disclosed design of the harvester increases the speed with which a harvester comprising a baling mechanism moves a bale from a bale chamber to a second position from which the bale will exit the harvester. Instead of relying solely on the passive nature of the angle of a bottom conveyor and gravity to transfer the bale, the current design includes a bottom conveyor with baling belts that assume a variable geometry during different stages of operations that coordinate faster, controlled movement of the baling belts from one position to a position immediately prior to exit or evacuation from the harvester. The instantly disclosed design also preserves the shape of the bale during transition from a first position to a second position by exacting tension on the bale at appropriate points of the bale during transfer. By correcting the shape of the bale, the instantly disclosed design improves bale density over prior designs during transition from a first position to a second position. Lastly, the design shortens the transfer time of the bale from the first bale chamber during transition.